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<a href="#var-members">Variables</a>  </div>
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<div class="title">Complex FFT Tables</div>  </div>
<div class="ingroups"><a class="el" href="group__group_transforms.html">Transform Functions</a></div></div>
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<tr><td colspan="2"><h2><a name="var-members"></a>
Variables</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">const uint16_t&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group___c_f_f_t___c_i_f_f_t.html#gae247e83ad50d474107254e25b36ad42b">armBitRevTable</a> [1024]</td></tr>
<tr><td class="memItemLeft" align="right" valign="top">const <a class="el" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715">float32_t</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group___c_f_f_t___c_i_f_f_t.html#gaa29400b1efb778cd88c3ba1bb19eb339">twiddleCoef</a> [6144]</td></tr>
<tr><td class="memItemLeft" align="right" valign="top">const <a class="el" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0">q31_t</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group___c_f_f_t___c_i_f_f_t.html#ga80f8f038faf4289eebc59dd5fa010993">twiddleCoefQ31</a> [6144]</td></tr>
<tr><td class="memItemLeft" align="right" valign="top">const <a class="el" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea">q15_t</a> ALIGN4&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group___c_f_f_t___c_i_f_f_t.html#ga39e78f61a5f4bd5cfb577b11099a2c7f">twiddleCoefQ15</a> [6144]</td></tr>
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<hr/><h2>Variable Documentation</h2>
<a class="anchor" id="gae247e83ad50d474107254e25b36ad42b"></a><!-- doxytag: member="arm_common_tables.c::armBitRevTable" ref="gae247e83ad50d474107254e25b36ad42b" args="[1024]" -->
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          <td class="memname">const uint16_t <a class="el" href="group___c_f_f_t___c_i_f_f_t.html#gae247e83ad50d474107254e25b36ad42b">armBitRevTable</a>[1024]</td>
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<dl class="user"><dt><b></b></dt><dd>Pseudo code for Generation of Bit reversal Table is </dd></dl>
<dl class="user"><dt><b></b></dt><dd><pre>for(l=1;l &lt;= N/4;l++)    
 {    
   for(i=0;i&lt;logN2;i++)    
   {     
     a[i]=l&amp;(1&lt;&lt;i);    
   }    
   for(j=0; j&lt;logN2; j++)    
   {    
     if (a[j]!=0)    
     y[l]+=(1&lt;&lt;((logN2-1)-j));    
   }    
   y[l] = y[l] &gt;&gt; 1;    
  } </pre> </dd></dl>
<dl class="user"><dt><b></b></dt><dd>where N = 4096 logN2 = 12 </dd></dl>
<dl class="user"><dt><b></b></dt><dd>N is the maximum FFT Size supported </dd></dl>

<p>Referenced by <a class="el" href="group___radix2___c_f_f_t___c_i_f_f_t.html#gac9565e6bc7229577ecf5e090313cafd7">arm_cfft_radix2_init_f32()</a>, <a class="el" href="group___radix2___c_f_f_t___c_i_f_f_t.html#ga5c5b2127b3c4ea2d03692127f8543858">arm_cfft_radix2_init_q15()</a>, <a class="el" href="group___radix2___c_f_f_t___c_i_f_f_t.html#gabec9611e77382f31e152668bf6b4b638">arm_cfft_radix2_init_q31()</a>, <a class="el" href="group___radix4___c_f_f_t___c_i_f_f_t.html#gaf336459f684f0b17bfae539ef1b1b78a">arm_cfft_radix4_init_f32()</a>, <a class="el" href="group___radix4___c_f_f_t___c_i_f_f_t.html#ga0c2acfda3126c452e75b81669e8ad9ef">arm_cfft_radix4_init_q15()</a>, and <a class="el" href="group___radix4___c_f_f_t___c_i_f_f_t.html#gad5caaafeec900c8ff72321c01bbd462c">arm_cfft_radix4_init_q31()</a>.</p>

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<a class="anchor" id="gaa29400b1efb778cd88c3ba1bb19eb339"></a><!-- doxytag: member="arm_common_tables.c::twiddleCoef" ref="gaa29400b1efb778cd88c3ba1bb19eb339" args="[6144]" -->
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          <td class="memname">const <a class="el" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715">float32_t</a> <a class="el" href="group___c_f_f_t___c_i_f_f_t.html#gaa29400b1efb778cd88c3ba1bb19eb339">twiddleCoef</a>[6144]</td>
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<dl class="user"><dt><b></b></dt><dd>Example code for Floating-point Twiddle factors Generation: </dd></dl>
<dl class="user"><dt><b></b></dt><dd><pre>for(i = 0; i&lt; 3N/4; i++)    
 {    
	twiddleCoef[2*i]= cos(i * 2*PI/(float)N);    
	twiddleCoef[2*i+1]= sin(i * 2*PI/(float)N);    
 } </pre> </dd></dl>
<dl class="user"><dt><b></b></dt><dd>where N = 4096 and PI = 3.14159265358979 </dd></dl>
<dl class="user"><dt><b></b></dt><dd>Cos and Sin values are in interleaved fashion </dd></dl>

<p>Referenced by <a class="el" href="group___radix2___c_f_f_t___c_i_f_f_t.html#gac9565e6bc7229577ecf5e090313cafd7">arm_cfft_radix2_init_f32()</a>, and <a class="el" href="group___radix4___c_f_f_t___c_i_f_f_t.html#gaf336459f684f0b17bfae539ef1b1b78a">arm_cfft_radix4_init_f32()</a>.</p>

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<a class="anchor" id="ga39e78f61a5f4bd5cfb577b11099a2c7f"></a><!-- doxytag: member="arm_common_tables.c::twiddleCoefQ15" ref="ga39e78f61a5f4bd5cfb577b11099a2c7f" args="[6144]" -->
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          <td class="memname">const <a class="el" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea">q15_t</a> ALIGN4 <a class="el" href="group___c_f_f_t___c_i_f_f_t.html#ga39e78f61a5f4bd5cfb577b11099a2c7f">twiddleCoefQ15</a>[6144]</td>
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<div class="memdoc">
<dl class="user"><dt><b></b></dt><dd>Example code for Q15 Twiddle factors Generation:: </dd></dl>
<dl class="user"><dt><b></b></dt><dd><pre>for(i = 0; i&lt; 3N/4; i++)    
 {    
	twiddleCoefQ15[2*i]= cos(i * 2*PI/(float)N);    
	twiddleCoefQ15[2*i+1]= sin(i * 2*PI/(float)N);    
 } </pre> </dd></dl>
<dl class="user"><dt><b></b></dt><dd>where N = 4096 and PI = 3.14159265358979 </dd></dl>
<dl class="user"><dt><b></b></dt><dd>Cos and Sin values are interleaved fashion </dd></dl>
<dl class="user"><dt><b></b></dt><dd>Convert Floating point to Q15(Fixed point 1.15): round(twiddleCoefQ15(i) * pow(2, 15)) </dd></dl>

<p>Referenced by <a class="el" href="group___radix2___c_f_f_t___c_i_f_f_t.html#ga5c5b2127b3c4ea2d03692127f8543858">arm_cfft_radix2_init_q15()</a>, and <a class="el" href="group___radix4___c_f_f_t___c_i_f_f_t.html#ga0c2acfda3126c452e75b81669e8ad9ef">arm_cfft_radix4_init_q15()</a>.</p>

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<a class="anchor" id="ga80f8f038faf4289eebc59dd5fa010993"></a><!-- doxytag: member="arm_common_tables.c::twiddleCoefQ31" ref="ga80f8f038faf4289eebc59dd5fa010993" args="[6144]" -->
<div class="memitem">
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          <td class="memname">const <a class="el" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0">q31_t</a> <a class="el" href="group___c_f_f_t___c_i_f_f_t.html#ga80f8f038faf4289eebc59dd5fa010993">twiddleCoefQ31</a>[6144]</td>
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<div class="memdoc">
<dl class="user"><dt><b></b></dt><dd>Example code for Q31 Twiddle factors Generation:: </dd></dl>
<dl class="user"><dt><b></b></dt><dd><pre>for(i = 0; i&lt; 3N/4; i++)    
 {    
    twiddleCoefQ31[2*i]= cos(i * 2*PI/(float)N);    
    twiddleCoefQ31[2*i+1]= sin(i * 2*PI/(float)N);    
 } </pre> </dd></dl>
<dl class="user"><dt><b></b></dt><dd>where N = 4096 and PI = 3.14159265358979 </dd></dl>
<dl class="user"><dt><b></b></dt><dd>Cos and Sin values are interleaved fashion </dd></dl>
<dl class="user"><dt><b></b></dt><dd>Convert Floating point to Q31(Fixed point 1.31): round(twiddleCoefQ31(i) * pow(2, 31)) </dd></dl>

<p>Referenced by <a class="el" href="group___radix2___c_f_f_t___c_i_f_f_t.html#gabec9611e77382f31e152668bf6b4b638">arm_cfft_radix2_init_q31()</a>, and <a class="el" href="group___radix4___c_f_f_t___c_i_f_f_t.html#gad5caaafeec900c8ff72321c01bbd462c">arm_cfft_radix4_init_q31()</a>.</p>

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